Chinese Font Project

Building a High-Speed Experience: A Comprehensive Analysis of the 字图 CDN Deployment Architecture

In today's internet era, Content Delivery Networks (CDN) have become a key technology for enhancing website performance and user experience. As a free font CDN built under the 中文网字计划 (Chinese Web Font Project), 字图 CDN needs to provide nearly 150GB of bandwidth monthly while remaining free for users. This article will detail the deployment architecture of 字图 CDN, helping you better understand and replicate our technology.

What is 字图 CDN, and what problems does it solve?

字图 CDN is not a traditional CDN; it is a solution that manages a large number of CDN clusters, behaving similarly to conventional CDNs.

  1. Global Distribution: By caching and distributing text and image content through globally distributed server nodes, 字图 CDN reduces user access latency, improves website loading speed, and enhances user experience.
  2. Gateway Control: It provides advanced features such as request forwarding, load balancing, and security authentication through gateway servers.
  3. Origin Control: Content distribution is controlled via origin servers, allowing for a strong management of caching strategies.

Deployment Architecture of 字图 CDN

The deployment architecture of 字图 CDN mainly consists of the following components:

Edge Computing Gateway

The edge computing gateway plays a critical role in 字图 CDN, offering high availability and high-performance request forwarding, load balancing, and security authentication. We chose Deno Deploy as our platform, which not only offers excellent performance and a free tier but also simplifies the deployment process; you can complete deployment in just a few lines of code and a click, with version changes and fixes accomplished within minutes.

Users first access our edge computing gateway via a URL, and the gateway assigns them to a specified sub-CDN based on various strategies.

Request Forwarding

The link users access for the CDN remains consistent, eliminating user awareness of the sub-CDN's existence and reducing user experience issues stemming from CDN failures. When a sub-CDN encounters a problem, we can swiftly remove it from the code and complete deployment within minutes. This design enhances system robustness and ensures continuity in user experience.

Load Balancing

We utilize advanced load balancing algorithms to distribute requests across different CDN nodes based on the request's originating IP, thereby increasing CDN cache rates and usage. By adjusting the load balancing algorithms, we can offer a range of strategies for adjusting sub-CDN traffic distribution and traffic limits. For example, we can dynamically adjust traffic allocation based on geographic location, network conditions, and server load to achieve optimal resource utilization and user experience.

Security Authentication

To prevent attacks and abuse from malicious users, we have integrated a multi-layered security authentication mechanism into the edge computing gateway. For unfriendly users, we can limit their access by returning error responses, preventing them from reaching our sub-CDN. In the future, we may also issue tokens to control users' usage quotas, further enhancing the system's security and control.

CDN Service Providers (Various Sub-CDNs)

CDN service providers are the core functional components of 字图 CDN. Given that the features of each CDN service provider might go offline and be unstable at any moment, we require multiple CDN service providers to mitigate the impact of individual CDN failures. Currently, we use ImageKit, which provides comprehensive CDN services, allowing for direct origin setup; deploying a new CDN takes just a few minutes and is easily scalable.

The integration of CDN service providers with the edge computing gateway enables dynamic CDN load balancing and traffic control, offering significant convenience.

Origin Servers

The origin servers store the original font content. When users request content, the sub-CDN fetches it from the origin server and caches it locally for subsequent requests, reducing the load on the origin servers. The origin servers for the 中文网字计划 are deployed on Netlify, which automatically builds from chinese-free-web-font-storage using CICD. Netlify offers a monthly quota of 1TB, which is nearly never exhausted.

Conclusion

The deployment architecture of 字图 CDN achieves efficient distribution of text and image content through coordination among origin servers, CDN nodes, DNS resolution, caching strategies, and security measures. By properly deploying 字图 CDN, enterprises and developers can significantly enhance website performance and user experience, increasing the availability and security of content.